This invention relates to a reaction sintered carbide/metal product, optionally incorporating diamond, characterized by improved sinterability and strength and by the ability to optimize its physical properties for a wide variety of applications.
Reaction sintering as employed herein refers to a consolidation process in which one or more constituent substances undergo a chemical reaction to form one or more reaction products, said reaction enhancing the sintering process and said reaction product or products becoming a useful constituent of the sintered body.
Embodiments of this invention incorporating residual diamond may be characterized as sintered carbide/diamond products. The invention therefore relates to the field of sintered diamond products useful for cutting tools and the like. By sintered diamond is meant a sintered body incorporating diamond, usually with one or more additional constituents functioning as binders or sintering aids.
Sintered diamond products are useful in the production of sintered composite products comprising an active layer containing said sintered diamond product bonded to and supported by a stronger material, such as cobalt-cemented tungsten carbide. One embodiment of the invention, characterized by zero diamond content or by low diamond content, is useful as a bonding layer between said substrate and said active layer. An embodiment of the invention characterized by intermediate diamond content is useful as a transition layer between said substrate and said active layer, or between said bonding layer and said active layer. An embodiment of the invention characterized by high diamond content is useful as said active layer per se. Those embodiments of the invention which incorporate diamond should not be confused with the product known in the art as polycrystalline diamond or PCD. PCD is employed herein to refer to a sintered diamond product wherein diamond is the major constituent and substantially all of the diamond crystals are directly bonded to adjacent diamond crystals.